Trucks, truck trailers and large shipping or cargo containers are generally of the type having a rectangular configuration with two parallel longitudinal side walls and two parallel end walls. One of the end walls typically includes pivoted double doors to facilitate loading and unloading of the truck trailer compartment. While this type of door is capable of facilitating loading operations, the opening it provides is limited in size to the dimensions of the end wall, and thus is inconvenient for loading certain types of cargo.
Special cargo, or special delivery cargo, also requires a greater degree of access to the interior than can be provided by pivoted double doors located on the smaller end wall of the truck trailer. Large heavy cargo, for example, may be difficult and time consuming to load into the truck trailer via the end wall opening. Where delivery of the cargo is required to be made directly to a construction site or other location where the cargo will be used directly, loading equipment and/or personnel may be sufficiently limited as to make the unloading operation quite difficult.
In the past, systems which have been used to provide interior container access via the longitudinal side walls instead of the one end wall, have made use of pivoted single and double doors, as well as doors comprising a flexible curtain. Curtain doors or "curtainside" access systems have consisted of longitudinally as well as vertically moving curtains. One example of a horizontally movable curtain system is shown in U.S. patent application Ser. No. 053,278, filed May 21, 1987.
While these types of curtainside systems have had the advantage of providing extensive load access to the truck trailer interior, one disadvantage has been inadequate hardware for tensioning the curtains and inadequate security techniques for securing the hardware once the curtain is in a closed and tensioned position.